Marine diesel lubricant



United States Patent MARINE DIESEL LUBRICANT Filed'Jan. 25, 1956, Ser. No. 561,344

2 Claims. (Cl. 252-3o3.4)

No Drawing.

This invention relates to lubricants for diesel engines. It is more particularly concerned with lubricants for marine diesels in which sour fuel oils are used as fuels.

As is well known to those familiar with the art, many types of large marine diesel engines are lubricated by injecting small amounts of a lubricant into the cylinder during each cycle. Such engines do not have conventional crank case type of lubrication wherein the continuous, copious lubrication of the pistons and cylinder walls iseffected. As is further known, many of these engines burn fuels usually of the No. 6 Bunker fuel type that contain relatively large amounts of sulfur and other corrosive materials. As a result, when these oils are burned in the cylinder, there are formed quantities of corrosive acidic compound,- such as sulfuric acid, sulfurous acid, etc. The presence of these materials is detrimental to the operational life of the engine because corrosion is increased and also because the presence of large amounts of strong acid promotes deposit formation and induces greater wear of the pistonand of the cylinder walls.

Accordingly, it will be appreciated that it would be highly advantageous to neutralize the acidic sulfur compounds and to eliminate the corrosive effects thereof so that engine life can be prolonged. It is to be noted that the use of conventional high detergency lubricating oils has not proved to be wholly effective. Indeed, in the cases where such oils may be effective, it has been necessary to use suchhigh concentrations of detergents that the overall operation is uneconomical.

It has now been found that corrosion and wear in the operation of marine diesels can be reduced effectively and economically. It has now been discovered that the effects of harmful deposits in'marine diesels can be overcome by lubricating the engines with a novel emulsion type lubricant that tends to neutralize acidic corrosive materials and to remove them from the combustion section of the engine.

Accordingly, it is an object of this invention to reduce corrosion in marine diesel operation. Another object is to provide a lubricant that will satisfactorily neutralize acidic corrosive combustion products and remove them from the cylinder. A more specific object is to provide an emulsion type lubricant that will overcome the harmful effects of corrosive agents while still maintaining effective lubrication of a marine diesel. Other objects and advantagesof this invention will become apparent to those skilled in the art from the following detailed description.

In general, the present invention provides an emulsion type lubricant for marine diesels which comprises, by weight of the lubricant, between about 10 percent and about 50 percent water (preferably between about 10 and about 35 percent), between about 80 percent and about 45 percent mineral lubricating oil (preferably between about 80 and about 55 percent), between about 1 'percent and about percent alkali-metal hydroxide, the amount thereof being suflicient to effect a total Base Number in the lubricant of between about and about 100, between about 1 percent and about 10* percent oilsoluble detergent and between about 3 percent and about 10 percent of an emulsifier that effects water-in-oil type emulsion.

The lubricants of this invention are prepared by dissolving an alkali-metal hydroxide in the water and the oil soluble detergent in the mineral lubricating oil. The aqueous and the oil solution are then emulsified by the addition of a suitable water-in-oil type emulsifying agent by any conventional means. Thus, for example, the emulsion can be produced by agitation in any suitable homogenizing equipment, such as a Manton-Gaulin Homogenizer, a Stratco Contactor, or in a mechanically agitated, heated blending kettle.

The basic materials that are dissolved in theaqueous phase of the lubricant are the alkali metal hydroxides. In general, lithium hydroxide is preferred because of the lower molecular weight. However, sodium and potassium hydroxides are effective. The amount of alkalimetal compound used will be between about one percent and about '5 percent, by weight of finished lubricant. Sufiicie'nt must be used, however, toproduce a total Base Number (ASTM Test D664-54) of 10-100, preferably 10-50.

The mineral oil content of the lubricant ofthis invention Will be the usual 'hydrocarbonlubricant utilizable for the lubrication of heavy machinery. Generally, this lubricating oil will be a petroleum hydrocarbon fraction or a blend of two or more fractions, of the No. 20 to No. 50 SAE grade. In terms of Saybolt Universal viscosity, the mineral oil will have a viscosity of 45-100 seconds at 210 F.,- and preferably'of 80 seconds at 210 F. The mineral lubricating oil can be obtained from any crude source or sources. It is especially preferred, however; to use a naphthenic oil, such asone obtained from acoastal crude.

The detergents that are dissolved or dispersed in the oil phase are, in general, the additives used in detergent motor oils. -Usua-lly they are polyvalent metal salts of organic acids. Non-limiting examples include petroleum sulfonates, such-asbarium mahogany sulfonate, magnesium {petroleum sulfonate, etc; wax-substituted aryl sulfonates, such as barium di-wax'benzene sulfonate, calcium tri-wax benzene sulfonate, barium wax naphthalene sulfonate, etc.; sulfurized or unsulfurized phenates and carboxylates, such as sulfurized calcium phenate, barium wax phenate, magnesium wax benzene carboxylate, etc. The detergents are not exactly equivalent and the selection of a particular detergent will depend upon the emulsifier used. Some detergents will destroy the emulsion characteristics with some emulsifiers, but will be found to be compatible with others.

As has been mentioned hereinbefore, the oil phase and the aqueous phase are maintained in a stable water-inoiI emulsion by means of a suitable emulsifying agent. In general the emulsifying agent can be a sulfonate, such as sodium mahogany sulfonate, ammonium naphthalene sulfonate, etc.;:ester-s of high molecular weight acids obtained-by controlled oxidation of petroleum fractions; fatty acid soaps, such as sodium oleate, red oil soaps, potassium stearate, ammonium linoleate, etc.; and the like. The preferred type of emulsifiers are a nonemetallic material, such as the ammonium soaps and the oxidized petroleum acid esters. It is to be understood, however, that emulsifying agents are not equally effective and that the effectiveness .ofa given emulsifying agent will be aifected by the types and the concentrations of the various other ingredients of the lubricant. The effectiveness of an emulsifying agent in any given formulation can readily be determined bythose skilled in the art by -sub jecting a sample to "anoven storage test at -436 F. A stable emulsionlubricant will not separate after 16 hours of storage.

The relative concentrations of the ingredients of the lubricant in this invention can vary over fairly wide ranges." Generally, thefa'moun tof basic material used be at least enough to eifectively reduce the acidity ,of the'corrosive combustion products. The amountof detergent used must be at least enough to provide eflective detergent action, whi le the amount of emulsifier will be suflicient'tomaintairra stable water-in-oil emulsion.

It has been found that the ranges within which the concentration of the various components of the emulsion type lubricant of this invention can be varied are within the following ranges, based upon the weight of the finished'lubricant: C

. Percent Basic? compound s t 5 Detergent w p Emulsif er l 7 3-10 3 Mineral lubricating oil 80-45 Water v 10-50 It is to be. understood that'the lubricant of this invention can'contain other additivesfor the purpose of ima parting other properties to the lubricant. Thus, 'for example, there can be added anti-rust agents,E.P. (extreme pressure) agents, antioxidants, and the like. v 7

Example :1 iInto a kettle equippedwith a'nnechanical agitator,'were placed 5 parts, by weight, of an emulsifier (Alox 16 57), 2 parts, by weight, of a detergent (Lubrizol 1220), and 60 parts, by weight, of a mineral lubricating oil. The emulsifier, Alox 1657, is a mixture of esters of high molecular weight acids obtained by controlled oxidation of petroleum oil, that is sold by the Alex Corp., Niagara Falls, New York. .A lox 1657 has the follow ing typical properties; i

A.P.I. gravity 17.6 SUS viscosity at 100 F 2,247 SUS viscosity at 130 F 868 SUS- viscosity'at 210 F 168.5 Viscosity in 112 Total base No 40 This lubricant was placed aboard a commercial motor vessel that was powered with an 8 cylinder, 2 cycle, double acting Gotaverkin diesel engine. This ship was op; erated continuously for seven days coastal voyages "During this time, two cylinders were lubricated ;with .the emulsion lubricant of this example and six cylinders were lubricated with astandard'marine lubricant ofithe mineral oil type This oilwas a blend of 57 volume percent solvent refined coastal oil of 150 seconds Saybolt at 210 F. and 43 volume percent solvent refined coastal oil of 55 seconds Saybolt at 210 F. It had an A.P.I.' gravity of 24 and a Saybolt viscosityjat' 210 F. of 97 seconds. At the completion of the run, it was found that the cylinders'lubricated' with the emulsion type lubricant operated'freely and had received adequate lubrication. 3 I a a a V This application is a continuation-impart of copend ing application Serial No. 541,847, fil ed October 20, 1955, and now abandoned. a a 1 Although the present invention'has been described with preferred embodiments, it isto be unders'oodthat modifications'and variations may be resorted to, without departing from the spirit and scopeof this invention, a those skilled in the art will readily understand. Such variations and modifications are considered tobe within the purview and scope of the appended claims.

We claim: a f I r '1. An emulsion lubricant for marine dieselsjwhich consists of, by weight of the lubricant, between about 10 percent and about percent water, between about 80 percent and about 55 percent minerallubricating oil having a Saybolt Universal viscosity of between about Further details astothe nature and properties of: this material are available in Alox Technical Data Sheet on 'Alox L -16 57, April 1952. The detergent, Lubrizol 1220, is a calcium petroleum sulfonate sold by the Lubrizol Corp., Cleveland, Ohio. The mineral lubricating oil is a. blend containing 38 volume percent of a solvent refined coastal oil having a Saybolt viscosity of 150 seconds at 210 F. and 62 volume'percent of a solvent refined coasta1 oil having a Saybolt viscosity of 55 seconds at 210 F. This blend has an A.P .I. gravity of 24 degrees and a Saybolt viscosity of about 75 seconds at 210 F. The mixture of oil detergent and emulsifier washeated with agitation at 130 F. until the solution was complete. It was then cooled to 100-1 10 F. .In a separate vessel was 'dissolved three parts by weight of lithium hydroxide monohydrate in thirty parts by weight of water. 7 V This solution was slowly added to the oil blend in the blending kettle. Continuous vigorous agitation was maintained throughout the blendingperiod After all the lithium hydroxide solution had been added vigorous agitation was continued for an additional 15 minutes in order to obtain the emulsion. This emulsion was then passed through 'a Manton-Gaulin Homogenizeroperated at 3000 to 3500 pounds .p.s,i.g.. Continuous agitation was maintained in the blending kettle while the emulsion was being transferred tothehomogenizer. f i' a 7 i 1 The water-in-oil emulsion lubricant thus producedhad the tollowing ph a1r=1 stics v 75 seconds and about seconds measuredat'210 'F.; between about 1 percent and about 5 percent alkali-metal hydroxide, said alkali-metal hydroxide being present in the water phase of said lubricant, the amount thereof being suffi'cient to effect a total base number in the lubn'cant of between about 10 and about 50, between aboutl percent and about 10 percentoil soluble polyvalent metal sulfonate and between about 3 percent and about 10 percent esters of high molecular weight acids obtained by controlled oxidation of petroleum oil. 1 V

2. An emulsion lubricant for'marine diesels which consists of, by weight of the lubricanhabout 30 percent water, about 60 percent naphthenic-mine'ral lubricating oil having a Saybolt Universal viscosity of about 75 sec: onds measured at 210 F.,= about 5 percent lithium ,hydroxide, said lithium hydroxide beingv present in the water'phase of said lubricant, about 2 percent. calcium petroleum sulfonate, and about 3 percent esters of high molecular weight acids obtained by controlled oxidation of petroleum oil; said oil lubricant having a total base number of about 40.

References Cited in the file 0f this patent i a UNITED STATES PATENTS 2,079,051 Sullivan et al. L- May. 4,. 1937 2,320,263 Carlsonet al. May 25, 1943 2,671,758 Vinogradet al.". Mar. 9,1954 2,727,005 McKinley et a1. Dec. 13,195 2,744,870 Stillebroer et al. :May. 3,1 1956, 2,820,007- van Der Minne et al- -J an.: 1 4,

,QTHER R FERENC S" Alox Corporation Technical Data sheet on Alo x 1657, April 1952, pub., byAlox Corp.,' 7 0 I "ine Street N.-Y.N.;Y.,page 1. 5 I v 

1. AN EMULSION LUBRICANT FOR MARINE DIESELS WHICH CONSISTS OF, BY WEIFHT OF THE LUBRICANT, BETWEEN ABOUT 10 PERCENT AND ABOUT 35 PERCENT WATER, BETWEEN ABOUT 80 PERCENT AND ABOUT 55 PERCENT MINERAL LUBRICATING OIL HAVING A SAYBOLT UNIVERSAL CISCOSITY OF BETWEEN ABOUT 75 SECONDS AND ABOUT 80 SECONDS MEASURED AT 210* F., BETWEEN ABOUT 1 PERCENT AND ABOUT 5 PERCENT ALKALI-METAL HYDROXIDE, SAID ALKALI-METAL HYDROXIDE BEING PRESENT IN THE WATER PHASE OF SAID LUBRICANT, THE AMOUNT THEREOF BEING SUFFICIENT TO EFFECT A TOTAL BASE NUMBER IN THE LUBRICANT OF BETWEEN ABOUT 10 AND ABOUT 50, BETWEEN ABOUT 1 PERCENT AND ABOUT 10 PERCENT OIL SOLUBLE POLYVALENT METAL, SULFONATE AND BETWEEN ABOUT 3 PERCENT AND ABOUT 10 PERCENT ESTERS OF HIGH MOLECULAR WEIGHT ACIDS OBTAINED BY CONTROLLED OXIDATION OF PETROLEUM OIL. 